A backlight module emitting approximate white light is used to illuminate a liquid crystal display (LCD) device to display actual images. The backlight module converts linear light sources such as cold cathode fluorescent lamp (CCFL), or point light sources such as light emitting diodes (LEDs), into area light sources having high uniformity and brightness. If LEDs are introduced as point light sources to the backlight module, the LEDs usually employ specific phosphor powder packed with light emitting diode chips for emitting the approximate white light.